Composting process of biological wastes is a biochemical process in which organic parts of biological wastes are decomposed by mesophilic or thermophilic micro organisms under the aerobic condition. The practice of composting has been carried out for centuries with very few analytical data having been reported on the relationship between the micro phased phenomena represented by the changes in micro organisms population and the dominant types of micro organisms, and the macro phased phenomena represented by the rates of weight loss, moisture and temperature increases. In order to develop or to design rapid composting systems, qualitative and quantitative data relating to the population and the succession of micro organisms, and the kinetics of the process during composting have to be investigated.The investigators developed an experimental composting system having a very small capacity(approximately 300mL)reactor, a temperature difference control unit, a temperature and weight measurem
… Moreent unit, and, a CO_2 analyzer. The relationship between micro and macro phased phenomena in the early stage of composting was investigated. The experimental results for macro phased phenomena indicated that the early stage consisted of two distinct reactions having two peaks of CO_2 evolution rates and that the temperature dependence of the two reactions was almost the same among various composting conditions. The trends were closely related with the micro phased phenomena represented by the characteristics of growth and decay of mesophilic or thermophilic micro organisms which were determined by bacterial cultures test.In the measurements of physico-chemical properties of compost materials, effects of moisture content and bulking agents on many property parameters were investigated.3)高温域で採取した試料を55、66℃で培養した結果、常温域からの叢遷移や最高温度を導く2回目の好気的分解との関連は明確でなかった。これは、実際のコンポスト化での2回目の分解時には、1回目によって栄養基質が消費されていて、本実験では潤沢な栄養培地条件を与えたためと考えられた。そこで、栄養濃度を薄めて制限した培養を行った結果、高温性の細菌や放線菌が認められ、細胞数増加特性も炭酸ガス発生速度変化と定性的に符合するものであった。4)実用施設でのコンポスト化においては、有機物分解の大部分が1次発酵の30日間に行われ、一方その他の材料物性変化はコンポスト化全期間にわたって緩慢に行われることが分かった。 Less